[llvm] r298489 - Revert "[ScalarEvolution] Predicate implication from operations"
Max Kazantsev via llvm-commits
llvm-commits at lists.llvm.org
Wed Mar 22 00:50:33 PDT 2017
Author: mkazantsev
Date: Wed Mar 22 02:50:33 2017
New Revision: 298489
URL: http://llvm.org/viewvc/llvm-project?rev=298489&view=rev
Log:
Revert "[ScalarEvolution] Predicate implication from operations"
This reverts commit rL298481
Fails clang-with-lto-ubuntu build.
Removed:
llvm/trunk/test/Analysis/ScalarEvolution/scev-division.ll
Modified:
llvm/trunk/include/llvm/Analysis/ScalarEvolution.h
llvm/trunk/lib/Analysis/ScalarEvolution.cpp
Modified: llvm/trunk/include/llvm/Analysis/ScalarEvolution.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/ScalarEvolution.h?rev=298489&r1=298488&r2=298489&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/ScalarEvolution.h (original)
+++ llvm/trunk/include/llvm/Analysis/ScalarEvolution.h Wed Mar 22 02:50:33 2017
@@ -978,20 +978,6 @@ private:
/// Test whether the condition described by Pred, LHS, and RHS is true
/// whenever the condition described by Pred, FoundLHS, and FoundRHS is
- /// true. Here LHS is an operation that includes FoundLHS as one of its
- /// arguments.
- bool isImpliedViaOperations(ICmpInst::Predicate Pred,
- const SCEV *LHS, const SCEV *RHS,
- const SCEV *FoundLHS, const SCEV *FoundRHS,
- unsigned Depth = 0);
-
- /// Test whether the condition described by Pred, LHS, and RHS is true.
- /// Use only simple non-recursive types of checks, such as range analysis etc.
- bool isKnownViaSimpleReasoning(ICmpInst::Predicate Pred,
- const SCEV *LHS, const SCEV *RHS);
-
- /// Test whether the condition described by Pred, LHS, and RHS is true
- /// whenever the condition described by Pred, FoundLHS, and FoundRHS is
/// true.
bool isImpliedCondOperandsHelper(ICmpInst::Predicate Pred, const SCEV *LHS,
const SCEV *RHS, const SCEV *FoundLHS,
@@ -1137,9 +1123,6 @@ public:
/// return true. For pointer types, this is the pointer-sized integer type.
Type *getEffectiveSCEVType(Type *Ty) const;
- // Returns a wider type among {Ty1, Ty2}.
- Type *getWiderType(Type *Ty1, Type *Ty2) const;
-
/// Return true if the SCEV is a scAddRecExpr or it contains
/// scAddRecExpr. The result will be cached in HasRecMap.
///
Modified: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolution.cpp?rev=298489&r1=298488&r2=298489&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp Wed Mar 22 02:50:33 2017
@@ -137,11 +137,6 @@ static cl::opt<unsigned> MaxSCEVCompareD
cl::desc("Maximum depth of recursive SCEV complexity comparisons"),
cl::init(32));
-static cl::opt<unsigned> MaxSCEVOperationsImplicationDepth(
- "scalar-evolution-max-scev-operations-implication-depth", cl::Hidden,
- cl::desc("Maximum depth of recursive SCEV operations implication analysis"),
- cl::init(4));
-
static cl::opt<unsigned> MaxValueCompareDepth(
"scalar-evolution-max-value-compare-depth", cl::Hidden,
cl::desc("Maximum depth of recursive value complexity comparisons"),
@@ -3423,10 +3418,6 @@ Type *ScalarEvolution::getEffectiveSCEVT
return getDataLayout().getIntPtrType(Ty);
}
-Type *ScalarEvolution::getWiderType(Type *T1, Type *T2) const {
- return getTypeSizeInBits(T1) >= getTypeSizeInBits(T2) ? T1 : T2;
-}
-
const SCEV *ScalarEvolution::getCouldNotCompute() {
return CouldNotCompute.get();
}
@@ -8541,137 +8532,19 @@ static bool IsKnownPredicateViaMinOrMax(
llvm_unreachable("covered switch fell through?!");
}
-bool ScalarEvolution::isImpliedViaOperations(ICmpInst::Predicate Pred,
- const SCEV *LHS, const SCEV *RHS,
- const SCEV *FoundLHS,
- const SCEV *FoundRHS,
- unsigned Depth) {
- // We want to avoid hurting the compile time with analysis of too big trees.
- if (Depth > MaxSCEVOperationsImplicationDepth)
- return false;
- // We only want to work with ICMP_SGT comparison so far.
- // TODO: Extend to ICMP_UGT?
- if (Pred == ICmpInst::ICMP_SLT) {
- Pred = ICmpInst::ICMP_SGT;
- std::swap(LHS, RHS);
- std::swap(FoundLHS, FoundRHS);
- }
- if (Pred != ICmpInst::ICMP_SGT)
- return false;
-
- auto GetOpFromSExt = [&](const SCEV *S) {
- if (auto *Ext = dyn_cast<SCEVSignExtendExpr>(S))
- return Ext->getOperand();
- return S;
- };
-
- // Acquire values from extensions.
- auto *OrigFoundLHS = FoundLHS;
- LHS = GetOpFromSExt(LHS);
- FoundLHS = GetOpFromSExt(FoundLHS);
-
- // Is a predicate can be proved trivially or using the found context.
- auto IsProvedViaContext = [&](ICmpInst::Predicate Pred,
- const SCEV *S1, const SCEV *S2) {
- return isKnownViaSimpleReasoning(Pred, S1, S2) ||
- isImpliedViaOperations(Pred, S1, S2, OrigFoundLHS, FoundRHS,
- Depth + 1);
- };
-
- if (auto *LHSAddExpr = dyn_cast<SCEVAddExpr>(LHS)) {
- // Should not overflow.
- if (!LHSAddExpr->hasNoSignedWrap())
- return false;
- auto *LL = LHSAddExpr->getOperand(0);
- auto *LR = LHSAddExpr->getOperand(1);
-
- // Checks that S1 >= 0 && S2 > RHS, trivially or using the found context.
- auto IsSumGreaterThanRHS = [&](const SCEV *S1, const SCEV *S2) {
- return IsProvedViaContext(ICmpInst::ICMP_SGT, S2, RHS) &&
- IsProvedViaContext(Pred, S1, getZero(RHS->getType()));
- };
- // Try to prove the following rule:
- // (LHS = LL + LR) && (LL >= 0) && (LR > RHS) => (LHS > RHS).
- // (LHS = LL + LR) && (LR >= 0) && (LL > RHS) => (LHS > RHS).
- if (IsSumGreaterThanRHS(LL, LR) || IsSumGreaterThanRHS(LR, LL))
- return true;
- } else if (auto *LHSUnknownExpr = dyn_cast<SCEVUnknown>(LHS)) {
- Value *LL, *LR;
- // FIXME: Once we have SDiv implemented, we can get rid of this matching.
- using namespace llvm::PatternMatch;
- if (match(LHSUnknownExpr->getValue(), m_SDiv(m_Value(LL), m_Value(LR)))) {
- // Rules for division.
- // We are going to perform some comparisons with Denominator and its
- // derivative expressions. In general case, creating a SCEV for it may
- // lead to a complex analysis of the entire graph, and in particular it
- // can request trip count recalculation for the same loop. This would
- // cache as SCEVCouldNotCompute to avoid the infinite recursion. This is a
- // sad thing. To avoid this, we only want to create SCEVs that are
- // constants in this section. So we bail if Denominator is not a constant.
- if (!isa<ConstantInt>(LR))
- return false;
-
- auto *Denominator = cast<SCEVConstant>(getSCEV(LR));
-
- // We want to make sure that LHS = FoundLHS / Denominator. If it is so,
- // then a SCEV for the numerator already exists and matches with FoundLHS.
- auto *Numerator = getExistingSCEV(LL);
-
- // Make sure that it exists and has the same type.
- if (!Numerator || Numerator->getType() != FoundLHS->getType())
- return false;
-
- // Make sure that the numerator matches with FoundLHs and the denominator
- // is positive.
- if (!HasSameValue(Numerator, FoundLHS) || !isKnownPositive(Denominator))
- return false;
-
- // Given that:
- // FoundLHS > FoundRHS, LHS = FoundLHS / Denominator, Denominator > 0.
- auto *Ty2 = getWiderType(Denominator->getType(), FoundRHS->getType());
- auto *DenominatorExt = getNoopOrSignExtend(Denominator, Ty2);
- auto *FoundRHSExt = getNoopOrSignExtend(FoundRHS, Ty2);
-
- // Try to prove the following rule:
- // (Denominator - 1 <= FoundRHS) && (RHS <= 0) => (LHS > RHS).
- // For example, given that FoundLHS > 2. It means that FoundLHS is at
- // least 3. If we divide it by Denominator <= 3, we will have at least 1.
- auto *DenomMinusOne = getMinusSCEV(DenominatorExt, getOne(Ty2));
- if (isKnownNonPositive(RHS) &&
- IsProvedViaContext(ICmpInst::ICMP_SLE, DenomMinusOne, FoundRHSExt))
- return true;
-
- // Try to prove the following rule:
- // (-Denominator <= FoundRHS) && (RHS < 0) => (LHS > RHS).
- // For example, given that FoundLHS > -3. Then FoundLHS is at least -2.
- // If we divide it by Denominator >= 3, then:
- // 1. If FoundLHS is negative, then the result is 0.
- // 2. If FoundLHS is non-negative, then the result is non-negative.
- // Anyways, the result is non-negative.
- auto *NegDenominator = getNegativeSCEV(DenominatorExt);
- if (isKnownNegative(RHS) &&
- IsProvedViaContext(ICmpInst::ICMP_SLE, NegDenominator, FoundRHSExt))
- return true;
- }
- }
-
- return false;
-}
-
-bool
-ScalarEvolution::isKnownViaSimpleReasoning(ICmpInst::Predicate Pred,
- const SCEV *LHS, const SCEV *RHS) {
- return isKnownPredicateViaConstantRanges(Pred, LHS, RHS) ||
- IsKnownPredicateViaMinOrMax(*this, Pred, LHS, RHS) ||
- IsKnownPredicateViaAddRecStart(*this, Pred, LHS, RHS) ||
- isKnownPredicateViaNoOverflow(Pred, LHS, RHS);
-}
-
bool
ScalarEvolution::isImpliedCondOperandsHelper(ICmpInst::Predicate Pred,
const SCEV *LHS, const SCEV *RHS,
const SCEV *FoundLHS,
const SCEV *FoundRHS) {
+ auto IsKnownPredicateFull =
+ [this](ICmpInst::Predicate Pred, const SCEV *LHS, const SCEV *RHS) {
+ return isKnownPredicateViaConstantRanges(Pred, LHS, RHS) ||
+ IsKnownPredicateViaMinOrMax(*this, Pred, LHS, RHS) ||
+ IsKnownPredicateViaAddRecStart(*this, Pred, LHS, RHS) ||
+ isKnownPredicateViaNoOverflow(Pred, LHS, RHS);
+ };
+
switch (Pred) {
default: llvm_unreachable("Unexpected ICmpInst::Predicate value!");
case ICmpInst::ICMP_EQ:
@@ -8681,34 +8554,30 @@ ScalarEvolution::isImpliedCondOperandsHe
break;
case ICmpInst::ICMP_SLT:
case ICmpInst::ICMP_SLE:
- if (isKnownViaSimpleReasoning(ICmpInst::ICMP_SLE, LHS, FoundLHS) &&
- isKnownViaSimpleReasoning(ICmpInst::ICMP_SGE, RHS, FoundRHS))
+ if (IsKnownPredicateFull(ICmpInst::ICMP_SLE, LHS, FoundLHS) &&
+ IsKnownPredicateFull(ICmpInst::ICMP_SGE, RHS, FoundRHS))
return true;
break;
case ICmpInst::ICMP_SGT:
case ICmpInst::ICMP_SGE:
- if (isKnownViaSimpleReasoning(ICmpInst::ICMP_SGE, LHS, FoundLHS) &&
- isKnownViaSimpleReasoning(ICmpInst::ICMP_SLE, RHS, FoundRHS))
+ if (IsKnownPredicateFull(ICmpInst::ICMP_SGE, LHS, FoundLHS) &&
+ IsKnownPredicateFull(ICmpInst::ICMP_SLE, RHS, FoundRHS))
return true;
break;
case ICmpInst::ICMP_ULT:
case ICmpInst::ICMP_ULE:
- if (isKnownViaSimpleReasoning(ICmpInst::ICMP_ULE, LHS, FoundLHS) &&
- isKnownViaSimpleReasoning(ICmpInst::ICMP_UGE, RHS, FoundRHS))
+ if (IsKnownPredicateFull(ICmpInst::ICMP_ULE, LHS, FoundLHS) &&
+ IsKnownPredicateFull(ICmpInst::ICMP_UGE, RHS, FoundRHS))
return true;
break;
case ICmpInst::ICMP_UGT:
case ICmpInst::ICMP_UGE:
- if (isKnownViaSimpleReasoning(ICmpInst::ICMP_UGE, LHS, FoundLHS) &&
- isKnownViaSimpleReasoning(ICmpInst::ICMP_ULE, RHS, FoundRHS))
+ if (IsKnownPredicateFull(ICmpInst::ICMP_UGE, LHS, FoundLHS) &&
+ IsKnownPredicateFull(ICmpInst::ICMP_ULE, RHS, FoundRHS))
return true;
break;
}
- // Maybe it can be proved via operations?
- if (isImpliedViaOperations(Pred, LHS, RHS, FoundLHS, FoundRHS))
- return true;
-
return false;
}
Removed: llvm/trunk/test/Analysis/ScalarEvolution/scev-division.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/ScalarEvolution/scev-division.ll?rev=298488&view=auto
==============================================================================
--- llvm/trunk/test/Analysis/ScalarEvolution/scev-division.ll (original)
+++ llvm/trunk/test/Analysis/ScalarEvolution/scev-division.ll (removed)
@@ -1,334 +0,0 @@
-; RUN: opt < %s -analyze -scalar-evolution | FileCheck %s
-
-declare void @llvm.experimental.guard(i1, ...)
-
-define void @test01(i32 %a, i32 %n) nounwind {
-; Prove that (n > 1) ===> (n / 2 > 0).
-; CHECK: Determining loop execution counts for: @test01
-; CHECK: Loop %header: backedge-taken count is (-1 + %n.div.2)<nsw>
-entry:
- %cmp1 = icmp sgt i32 %n, 1
- %n.div.2 = sdiv i32 %n, 2
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i32 %indvar, 1
- %exitcond = icmp sgt i32 %n.div.2, %indvar.next
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @test01neg(i32 %a, i32 %n) nounwind {
-; Prove that (n > 0) =\=> (n / 2 > 0).
-; CHECK: Determining loop execution counts for: @test01neg
-; CHECK: Loop %header: backedge-taken count is (-1 + (1 smax %n.div.2))<nsw>
-entry:
- %cmp1 = icmp sgt i32 %n, 0
- %n.div.2 = sdiv i32 %n, 2
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i32 %indvar, 1
- %exitcond = icmp sgt i32 %n.div.2, %indvar.next
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @test02(i32 %a, i32 %n) nounwind {
-; Prove that (n >= 2) ===> (n / 2 > 0).
-; CHECK: Determining loop execution counts for: @test02
-; CHECK: Loop %header: backedge-taken count is (-1 + %n.div.2)<nsw>
-entry:
- %cmp1 = icmp sge i32 %n, 2
- %n.div.2 = sdiv i32 %n, 2
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i32 %indvar, 1
- %exitcond = icmp sgt i32 %n.div.2, %indvar.next
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @test02neg(i32 %a, i32 %n) nounwind {
-; Prove that (n >= 1) =\=> (n / 2 > 0).
-; CHECK: Determining loop execution counts for: @test02neg
-; CHECK: Loop %header: backedge-taken count is (-1 + (1 smax %n.div.2))<nsw>
-entry:
- %cmp1 = icmp sge i32 %n, 1
- %n.div.2 = sdiv i32 %n, 2
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i32 %indvar, 1
- %exitcond = icmp sgt i32 %n.div.2, %indvar.next
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @test03(i32 %a, i32 %n) nounwind {
-; Prove that (n > -2) ===> (n / 2 >= 0).
-; TODO: We should be able to prove that (n > -2) ===> (n / 2 >= 0).
-; CHECK: Determining loop execution counts for: @test03
-; CHECK: Loop %header: backedge-taken count is (1 + %n.div.2)<nsw>
-entry:
- %cmp1 = icmp sgt i32 %n, -2
- %n.div.2 = sdiv i32 %n, 2
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i32 %indvar, 1
- %exitcond = icmp sge i32 %n.div.2, %indvar
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @test03neg(i32 %a, i32 %n) nounwind {
-; Prove that (n > -3) =\=> (n / 2 >= 0).
-; CHECK: Determining loop execution counts for: @test03neg
-; CHECK: Loop %header: backedge-taken count is (0 smax (1 + %n.div.2)<nsw>)
-entry:
- %cmp1 = icmp sgt i32 %n, -3
- %n.div.2 = sdiv i32 %n, 2
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i32 %indvar, 1
- %exitcond = icmp sge i32 %n.div.2, %indvar
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @test04(i32 %a, i32 %n) nounwind {
-; Prove that (n >= -1) ===> (n / 2 >= 0).
-; CHECK: Determining loop execution counts for: @test04
-; CHECK: Loop %header: backedge-taken count is (1 + %n.div.2)<nsw>
-entry:
- %cmp1 = icmp sge i32 %n, -1
- %n.div.2 = sdiv i32 %n, 2
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i32 %indvar, 1
- %exitcond = icmp sge i32 %n.div.2, %indvar
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @test04neg(i32 %a, i32 %n) nounwind {
-; Prove that (n >= -2) =\=> (n / 2 >= 0).
-; CHECK: Determining loop execution counts for: @test04neg
-; CHECK: Loop %header: backedge-taken count is (0 smax (1 + %n.div.2)<nsw>)
-entry:
- %cmp1 = icmp sge i32 %n, -2
- %n.div.2 = sdiv i32 %n, 2
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i32 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i32 %indvar, 1
- %exitcond = icmp sge i32 %n.div.2, %indvar
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @testext01(i32 %a, i32 %n) nounwind {
-; Prove that (n > 1) ===> (n / 2 > 0).
-; CHECK: Determining loop execution counts for: @testext01
-; CHECK: Loop %header: backedge-taken count is (-1 + (sext i32 %n.div.2 to i64))<nsw>
-entry:
- %cmp1 = icmp sgt i32 %n, 1
- %n.div.2 = sdiv i32 %n, 2
- %n.div.2.ext = sext i32 %n.div.2 to i64
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i64 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i64 %indvar, 1
- %exitcond = icmp sgt i64 %n.div.2.ext, %indvar.next
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @testext01neg(i32 %a, i32 %n) nounwind {
-; Prove that (n > 0) =\=> (n / 2 > 0).
-; CHECK: Determining loop execution counts for: @testext01neg
-; CHECK: Loop %header: backedge-taken count is (-1 + (1 smax (sext i32 %n.div.2 to i64)))<nsw>
-entry:
- %cmp1 = icmp sgt i32 %n, 0
- %n.div.2 = sdiv i32 %n, 2
- %n.div.2.ext = sext i32 %n.div.2 to i64
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i64 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i64 %indvar, 1
- %exitcond = icmp sgt i64 %n.div.2.ext, %indvar.next
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @testext02(i32 %a, i32 %n) nounwind {
-; Prove that (n >= 2) ===> (n / 2 > 0).
-; CHECK: Determining loop execution counts for: @testext02
-; CHECK: Loop %header: backedge-taken count is (-1 + (sext i32 %n.div.2 to i64))<nsw>
-entry:
- %cmp1 = icmp sge i32 %n, 2
- %n.div.2 = sdiv i32 %n, 2
- %n.div.2.ext = sext i32 %n.div.2 to i64
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i64 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i64 %indvar, 1
- %exitcond = icmp sgt i64 %n.div.2.ext, %indvar.next
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @testext02neg(i32 %a, i32 %n) nounwind {
-; Prove that (n >= 1) =\=> (n / 2 > 0).
-; CHECK: Determining loop execution counts for: @testext02neg
-; CHECK: Loop %header: backedge-taken count is (-1 + (1 smax (sext i32 %n.div.2 to i64)))<nsw>
-entry:
- %cmp1 = icmp sge i32 %n, 1
- %n.div.2 = sdiv i32 %n, 2
- %n.div.2.ext = sext i32 %n.div.2 to i64
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i64 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i64 %indvar, 1
- %exitcond = icmp sgt i64 %n.div.2.ext, %indvar.next
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @testext03(i32 %a, i32 %n) nounwind {
-; Prove that (n > -2) ===> (n / 2 >= 0).
-; TODO: We should be able to prove that (n > -2) ===> (n / 2 >= 0).
-; CHECK: Determining loop execution counts for: @testext03
-; CHECK: Loop %header: backedge-taken count is (1 + (sext i32 %n.div.2 to i64))<nsw>
-entry:
- %cmp1 = icmp sgt i32 %n, -2
- %n.div.2 = sdiv i32 %n, 2
- %n.div.2.ext = sext i32 %n.div.2 to i64
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i64 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i64 %indvar, 1
- %exitcond = icmp sge i64 %n.div.2.ext, %indvar
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @testext03neg(i32 %a, i32 %n) nounwind {
-; Prove that (n > -3) =\=> (n / 2 >= 0).
-; CHECK: Determining loop execution counts for: @testext03neg
-; CHECK: Loop %header: backedge-taken count is (0 smax (1 + (sext i32 %n.div.2 to i64))<nsw>)
-entry:
- %cmp1 = icmp sgt i32 %n, -3
- %n.div.2 = sdiv i32 %n, 2
- %n.div.2.ext = sext i32 %n.div.2 to i64
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i64 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i64 %indvar, 1
- %exitcond = icmp sge i64 %n.div.2.ext, %indvar
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @testext04(i32 %a, i32 %n) nounwind {
-; Prove that (n >= -1) ===> (n / 2 >= 0).
-; CHECK: Determining loop execution counts for: @testext04
-; CHECK: Loop %header: backedge-taken count is (1 + (sext i32 %n.div.2 to i64))<nsw>
-entry:
- %cmp1 = icmp sge i32 %n, -1
- %n.div.2 = sdiv i32 %n, 2
- %n.div.2.ext = sext i32 %n.div.2 to i64
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i64 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i64 %indvar, 1
- %exitcond = icmp sge i64 %n.div.2.ext, %indvar
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
-define void @testext04neg(i32 %a, i32 %n) nounwind {
-; Prove that (n >= -2) =\=> (n / 2 >= 0).
-; CHECK: Determining loop execution counts for: @testext04neg
-; CHECK: Loop %header: backedge-taken count is (0 smax (1 + (sext i32 %n.div.2 to i64))<nsw>)
-entry:
- %cmp1 = icmp sge i32 %n, -2
- %n.div.2 = sdiv i32 %n, 2
- %n.div.2.ext = sext i32 %n.div.2 to i64
- call void(i1, ...) @llvm.experimental.guard(i1 %cmp1) [ "deopt"() ]
- br label %header
-
-header:
- %indvar = phi i64 [ %indvar.next, %header ], [ 0, %entry ]
- %indvar.next = add i64 %indvar, 1
- %exitcond = icmp sge i64 %n.div.2.ext, %indvar
- br i1 %exitcond, label %header, label %exit
-
-exit:
- ret void
-}
-
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